of berlin



March 5, 1929 A. KNIG ET A1,.

Filed Jan. 11, 1927 vCD Patented Mar. 5, i929.

i einen eter carica.

ALFRED KNIGANDGERHARD MLLER, 0F BERLIN, GERMANY, ASSIGNORS TO THE FIRM STAATLICHE PORZELLAN MANUFAKTUR, OF BERLIN, GERMANY. A

Filmname ArrARa'rus.

Application 11ed..fanuary 11, 1927,v Serial No. 160,397, and in Germany January 19, 1926.

Our invention relates toV improvements in filtering apparatus, .and more particularly infiltering apparatus of the type in which a bottom part providing a funnel collecting the filtered material is provided with a set of filtering cups of different diameters each of which is adapted to be placed on the said bottom part. One of the objects of the improvements is to provide a. filtering apparatus of this class in which the cups separately placed on the bottom part are in tightenga gement therewith, and which can be manufactured at low cost. With this object in view our invention consists in vproviding the bottom part and all the cups respectively at their top and bottom with plane bearing faces, the YAdimensions ofthe said faces being such that the bearing face of any cup ofthe set placed .on the bottom part is in engagement with the bearing face formed on the bottom part. Other objects ofthe invention-will appear from the following description.'

For the purpose of explaining the invention two examples embodying the'same have been shown in the accompanying drawing, in which Vthe same reference characters have been used in all the views to indicate corresponding parts. In saidy drawing,

f Fig. 1,- is a vsectional elevation showing the Vbottom part of the filtering apparatus and the cup placed thereon,

Figs. 2 and 3, are similar sectional elevations showing other cups of the set belonging to the filtering yapparatus shown in Fig. 1,

Fig. 4, is aisectional elevation showing a modification of the bottom part and the cups, and r' l Fig. 5, is a sectional elevational showing a modification of the cups in which the cup is vprovided with an exchangeable filtering lbottom.v

Ink the example `shown in Figs. 1 to 3,'our improved ltering apparatus consistsV of a bottom part comprising-a tapering tubular portion 1, a conical portion 15, and a iiange 16 having a raisedv outer rim 14. 'Ihe said bottom part is adapted to be placed on a suitable vacuum apparatus such as a-bottle connected with la suctionapparatus or pump, a packing ring being placed between the tapering tubularportion 1 and the neck of the bottle. The-horizontal flange 16 is provided at vits top side with a plane annular bearing surfLCei 17. Y l

In Figs. 1 to 3 we have shown a set of three cups of different diameters. The diameter of the cup 3 shown in Fig. 1 is equal to or smaller than the inner diameter of the plane annular bearing surface 17, and in order to be able to support the cup 3 on the said bearing surface, it is formed with an outwardly directed horizontal flange 10 formed at its' bottom side with a plane bearing surface,

the outer diameter of the said fiange and Ydiameter of the said bearingV surface 17.

rihus the bearing surface 18 of the said cup is provided around the margin of the bottom of the cup, a flange or similar extension not being needed. 'Ihe cup 4 shown in Fig. 3 is larger in diameter than the outer diameter of the bearing surface 17 and the inner diameter of the rim 14,@and in order to be able to place the said cup on the bottom member, an inwardly directed yflange 11 is provided around the margin of the bottom of the cup, the configuration of the said ange being such thatv when placing the same on the bearing surface 17 it does not make contact with the inner and upper edge of the rim 14.

By providing the upwardly directed rim 14 the cups are safely supported on the bottom part, and'they are not liable to fall from the bottom part by careless handling.

' In thefiguies the cups are shown Ito be provided with foraminated bottoms. But we wish it .to be understood that the said foraminated bottom has been shown merely for the purpose of illustration, and that in some cases a bottom of porous material. is provided.'

In the example so far described the bearing surface 17 of the bottom part has been made of ordinary size sufficient to produce a tight engagement between the same and the cups, Lthe bearing faces of the cups being adaptedftothe saidbearing surface ofv the bottom part. In Fig. 4 we have shown a modification in .which the cups of the set are provided with bearing surfaces the sizes of which correspond to the diameters of the cups, and in which the bottom part is provided with an enlarged bearing surface the outer diameter of which is equal .to or larger than the outer diameter of the largest cup the bearing surface of the and its bearing surface, and the inner diameter of which is equal to or smaller than the inner diameter of the bearing surface of the smallest cup. In the said ligure the bottom parthas been indicated by the reference character 5. As shown the said bottom part is provided with a horizontal flange 19 of con'iparatively large diameter and forn'ied with a raised rim 20. The liltering cups 6, 7 and 8 of the set are different in diameter, and they are formed with bearing faces G', 7 andl 8 ihe outer diameters of which are equal to the outer diameters of the cups. The outer diameter of the largest bearing surface 6 is equal to or, profi erably,` smaller than the outer diameter of flange 19, and the inner diameter of the bearing face 8 of the smallest cup 8 is substantially equal to the upper diameter of the conical part of the bottom part 5. Should it be desired to place a smaller filtering cup 3 on the bottom part 5, the said cup will be provided with an out- Vvinarclly Y directed flange such as l0. In a similarV way, when using an exceptionally large iltering'cup the diameter of which eX- ceeds theinner diameter of the rim 20, a cup of the form shown in Fig. 3 may be used.

In F ig. 5 we have shown a cup 9 which is provided with an exchangeable filteringT bottom 12, the said bottom being placed on an annular shoulder 13. It will be understood that a filtering cup of this type may be used in lieu of any of the filtering cups 2, 3, i or 6, 7 8. By providing the kbottom part with a plane bearing surfacel adapted for engagement with the bearingfaces of all the cups of the set, the said bearing faces can be accurately manufactured or ground at low cost.

Vhile in describing the invention reference has been made to particular examples embodying the same, we wish it to lbe understood that our invention is not limited to the constructions shown in the drawing. F or eX- ample, we do not limit ourselves to the construction lof the cups provided with annular bearing planes, and that in some cases the said bearing faces are in the form of annular edges formed by beveled side walls.

7e claim:

1.. A filtering apparatus, comprising a bottom part having a plane bearing surface, and a filtering cup having a diameter larger than the outer diameter of said bearing surface and formed with a vfiltering bottom and with a flange tapering from the margin oi said 'filtering bottom downwardly and inwardly and having` at itsy bottom bearing face the youter diameter of which'is not larger than the outer diameter of the bearing surface of said bottom part and the inner diameter of which is smaller than the diameter ofsaid filtering bottom.

2. A filtering apparatus, comprising a bot,-

tom part having a plane marginal bearing surface, a raised rim surrounding said bearing surface, and a tubular portion projecting downwardly from said bearing surface, a filtering cup having a filtering bottom and larger in outer diameter than the inner diameter of said raised rim and formed with a marginal flange tapering downwardly and inwardly and having its bottom vpart Smaller in outer diameter than the inner diameter of said raised rim.

3. A filtering apparatus, comprising a bottom part having a bearing surface of large diameter and considerable area and adapted to be used in connection with any one of a set of ltering cups of differentl diameters and formed with bearing faces adapted' for engagement with the bearing surface of the bottom part.

Ll. A filtering apparatus, comprising a botl tom part having a bea-ring surface of large diameter and coi'isiderable area andk adapted to be used m connection with any one of a set of filtering cups of different diameters and formed at their bottoms withV marginal bearing faces, the outer diameter of said bearing surface of the bottom Ipart'being atv` least largest cup of the set, and the inner diameter of said bearing surface of the bottom part being smaller than the -outer diameter of the smallest cup of the set.y y

5. A filtering apparatus, comprising a bottom part having a bearing surface of large diameter and considerable area. and formed with an upwardly directed outer rim and adapted to be used in connection With'any one of a set of filtering cups of different diameters and formed with a filtering bottomv and marginal rims projecting downwardly from said bottom and' providingv bearing faces adapted for engagement with the bearing surface of the bottom part.

6. A filtering apparatus,comprising a bottom part having a bearing surface of large diameter and 'considerable area, adapted to be used in connection with any one of a set of filtering cups of different diameters formed with filtering bottoms and marginal signatures. p

ALFRED KONIG. GERHARD MLLER.y

equal to the outer diameter of the' 

